The present invention relates to a heat transfer container and more particularly to a portable single-use self-heating (or cooling) container for products including food and beverages and a method of making said container.
The present invention is primarily directed to a self-heating beverage container and method of making. It is understood, however, that the invention may also be practiced as a cooling unit and is suitable for any product, including beverages, food and the like.
It is generally known to provide a heat transfer container having a reaction cavity in heat conducting connection with the contents of the container. The reaction cavity is isolated from the contents and contains two separate chemical reactants which are individually stable and capable of an exothermic or endothermic reaction when combined within the cavity.
For example, U.S. Pat. No. 4,793,323 discloses a self-heating container, wherein a metallic product cup is suspended by its outer rim within a plastic reaction vessel. The reaction vessel is provided with a breakable barrier defining two chambers. Breaking members consisting of stems ending in projections are installed inside the reaction vessel and are capable of piercing the barrier when pushed from outside at a curved flexible bottom unitary to the reaction vessel. An outer insulating envelope surrounds the container and extends below the flexible bottom to provide a base for the container.
U.S. Pat. No. 5,626,022 discloses a container having a reaction module unitarily formed within the container. The reaction module contains a solid reactant. A liquid reactant is contained within a cap module disposed within an opening in the reaction module. The cap module has activation means which comprise an actuator disc and vertical prongs extending therefrom toward a breakable cap bottom. Initiation of a reaction, caused by combination of the reactants is achieved by depressing the actuator disc on the container cap causing the prongs within the cap to break the cap bottom releasing liquid into the reaction module.
Other heat transfer containers have a separate external barrier piercing device which must be inserted into the container""s reaction cavity from outside to initiate the desired chemical combination.
The prior art also discloses container covers having means for storing user dispensable additives. U.S. Pat. No. 5,431,276 discloses a container cover having storage compartments partially defined by an external rim and a concentric inner rim disposed under a circular top. A plurality of dividers extends between the rims to form compartments between the top and a penetrable bottom barrier attached under the rims and dividers. Within each compartment is a plunger capable of penetrating the bottom barrier when pressed from above the cap.
Existing containers, however, have significant drawbacks. They often require a large number of and/or structurally complex components, making them unnecessarily expensive and difficult to manufacture. Further, they do not recognize the need for nor provide important functional ergonomic and aesthetic features. They are therefore not suited to the objects of the present invention.
It would be desirable to have a disposable heat transfer container that is functionally superior while being simple of structure and highly suitable for economical large scale manufacture. It would also be desirable to have a heat transfer unit having improved aesthetic and functional ergonomic features.
Accordingly, a primary object of the present invention is to provide an improved heat transfer container and method of making the same.
It is another object of the invention to provide an improved single-use heat transfer container.
It is another object of the invention to provide a container structure and method of making suited to economical large-scale manufacture.
It is another object of the invention to provide a container having superior heat transfer and insulating properties in combination with desirable ergonomic and aesthetic features.
These and other objects of the present invention will be apparent from the following description, particular reference being made to the drawings.
Briefly, the aforementioned and other objects of the invention are accomplished by a portable single-use heat transfer container having a product body integral with a conductive internal reaction vessel. The product body is insulated by an outer jacket which partially defines a product chamber capable of storing a product such as beverage. The reaction vessel has a flange at an open lower end that is sealed to the lower interior surface of the product body so as to define the bottom of the product chamber. A flexible bottom member is sealed to the reaction vessel enclosing the open lower end. The bottom member has a pin extending from its internal surface toward a penetrable barrier isolating two reactants inside the reaction vessel. When the flexible member is depressed from outside the container, the pin breaks the barrier to combine the reactants and initiate the desired reaction. Thereafter, the contents of the product chamber will be temperature conditioned as desired. The container preferably also has a dispensing cover with user activated compartments holding product additives. The inventive method of making the heat transfer container is disclosed in the following detailed description of the invention.
The heat transfer container and method of manufacture according to the present invention provide an until now undiscovered combination of heat transfer functionality in a very simple structure especially directed to a novel and economical method of manufacture. The features of the present invention, including the dispensing cover and the flexible bottom member, have also been invented with ease of use in mind.